Scum — Defs

01 n. The extraneous matter or impurities which rise to the surface of liquids in boiling or fermentation, or which form on the surface by other …

1.
The extraneous matter or impurities which rise to the surface of liquids in boiling or fermentation, or which form on the surface by other means; also, the scoria of metals in a molten state; dross.
“Some to remove the scum as it did rise.” — Spenser.
2.
refuse; recrement; anything vile or worthless.
“The great and innocent are insulted by the scum and refuse of the people.” — Addison.

02 v. t. To take the scum from; to clear off the impure matter from the surface of; to skim.

imp. & p. p. Scummed; p. pr. & vb. n. Scumming

1.
To take the scum from; to clear off the impure matter from the surface of; to skim.
“You that scum the molten lead.” — Dryden & Lee.
2.
To sweep or range over the surface of.[Obs.]
“Wandering up and down without certain seat, they lived by scumming those seas and shores as pirates.” — Milton.

03 v. i. To form a scum; to become covered with scum. Also used figuratively.

1.
To form a scum; to become covered with scum. Also used figuratively.
“Life, and the interest of life, have stagnated and scummed over.” — A. K. H. Boyd.